Nasal Drug Delivery System and Devices: An Overview on Health Effects

For centuries, intranasal administration has been a perennial fascination for humanity. In recent times, the realm of nanotechnology-based biomaterials has witnessed a notable resurgence. At its epicenter is the concept of "nose-to-brain" delivery, a pivotal strategy within the pharmaceutical landscape aimed at circumventing the challenges of first-pass metabolism and the reticular endothelium system. This innovative approach spans a spectrum of domains, encompassing drug delivery, diagnostics, theranostics, photothermal and photodynamic therapies, bioengineering, and biomedical engineering. To overcome its multifaceted challenges, the pioneering development of novel formulations is paramount, utilizing the potential of mucoadhesive polymers, sol–gel techniques, pH-dependent absorption, and advanced methodologies. The evolution of excipient technologies has, however, raised concerns surrounding nasal irritation, rapid drainage, and systemic toxicity, affecting both established and emerging formulations. Furthermore, the growing interest in comprehending, evaluating, and documenting the toxicity profiles of nanomaterials stems from their vast range of applications across industries. It sheds light on the various toxicological implications arising from the myriad variables in dosage form formulations, including the role of excipients. It is crucial to note that the mishandling of devices designed for nasal formulation administration can significantly contribute to toxicity concerns. Given these notable developments, this comprehensive review aims to provide an exhaustive examination of current knowledge regarding the physiological consequences of intranasal drug delivery systems within the human body.